Lubricants for slideway surfaces such as work tables of machining tools are required to have lubricity in order to improve working accuracy. Then, in order to meet such a requirement, a lubricant to which additives such as an extreme pressure agent and an oiliness agent are blended is used. In addition, such lubricants are also required to have lubricity to a hydraulic pump as accessory equipment of a machining tool in terms of a proper operation of a machining tool, and a lubricant to which additives such as an extreme pressure agent and an oiliness agent are blended is used.
Examples of such additives include phosphoric acid esters, acidic phosphoric, acid esters, phosphorous acid esters, carboxylic acids, a sulfur compound and amines (see, for example, Patent Literature 1). In addition, there has been attempted to neutralize an acidic phosphoric acid ester by an alkyl amine to thereby result in the improvement in stability (see, for example, Patent Literature 2).
In addition, oiliness agents include amines such as monoamines, polyamines and alkanolamines (see, for example, Patent Literatures 2 and 3). Monoamines and polyamines are blended as a simple substance thereof (see, for example, Patent Literature 2). In addition, with respect to alkanolamines, a method in which they are used as a compound for forming a salt such as an amine salt with an acidic phosphoric acid ester or an amide with a carboxylic acid is described (see, for example, Patent Literature 3).